Participate with other selected investigators and the NHLBI in the development of a protocol to study survivors of documented myocardial farctions for determining whether the regular administration of Propranolol will result in a decrease in overall mortality over a two (2) year period. Specifically: Meet with other groups selected to participate in the PHT developing a definitive study protocol; In the sixth month, select and train staff for conduct of the trial for the recruitment phase which will begin in June 1978; and Notify local medical community of the study and finalize plans for patient recruitment.